In recent years, with the advent of Fin Field Effect Transistors (FinFETs), the integrated circuits using FinFETs have smaller sizes, faster switching speed and higher current density than integrated circuits using traditional Metal Oxide Semiconductor Field Effect Transistors (MOSFETs). With the rapid development of high technology industry, there is an increasing demand of further size-reduced integrated circuits using FinFETs and more cost efficient methods of manufacturing the integrated circuits using FinFETs.